Effect of Surrounding Pressures under Capsule-Free HIP and Vacuum Sinterings on Hardness of Sintered Porous Ni Compact

Abstract

The sintered porous Ni is very important as electrode materials and have been used widely. Then, in this work, the effect of the surrounding pressure under capsule-free HIP (CFHIP), vacuum sinterings on the hardness of the porous Ni compact sintered at 1073K, 1173K and 1273K for 1 hour was investigated. The results obtained were as follows. The volume shrinkage of the porous Ni compact sintered in CFHIP was lager than that of ones sintered in vacuum. The hardness of the porous Ni compact sintered in CFHIP was larger than in vacuum. The hardness of the sintered porous Ni compact formed from the smaller particle size powder was higher under the both surrouding pressures, CFHIP or vacuum, and at the each sintering temperature.